The objective of the study is to determine that the steady is reached for 3K-desogestrel and EE within each dosing phase. Once the steady state is attained, the objective is to determine that state serum levels are proportional to desogestrel dose (linear kinetics) during cycle 3 of CTR 99 or CTR 77 and that EE steady levels are similar under different co-administered Org desogestrel doses during cycle 3 of CTR 99 or CTR 77 (dose equivalency).